Single-acting two-stroke cycle internal-combustion engine



G. J. LUGT -ACTING TWO-STROKE CYCLE -COMBUSTION ENGINE July 25, 1950 SINGLE INTERNAL 2 Sheets-Sheet l Filed Dec. 30, 1947 .v i ..nWtr.S\.\\.\:.:. *u d n d #I l. a

July 25, 1950 2,516,708

G. J. LUGT SINGLE-ACTING TWO-STROKE CYCLE INTERNAL-COMBUSTION ENGINE Filed Deo. 50, 1947 2 Sheets-Sheet 2 Patented July 25, 1950 2,516,708 SINGLE-ACTING TWofsTRoiiE 'CYCL iNrnRNAncoMBUsTioN ENGINE Gerard Johan Lugt, Amsterdam, Netherlands, as

s ignor to Werkspoor N. V., a company of the Netherlands Application December 30, 1947, Serial No. 794,751 In the Netherlands May 26; 1943 section 1, Public Lew ezio, August 1946 Patent expires May 26, 1963 Claims.

The invention relates to a single acting two stroke internal combustion engine provided with across head, in which each cylinderv et the side of the crank shaft opens into a closed 'scavenging air chamber separated from the crankcase by a partition, said cylinder being provided with scav- Sr'eng ports withinsaid chamber, and theoutlet means of the cylinder being located at the cover side. This kind of internal combustion engineis wellk'nown and also usual for large engines, such as ship propulsion engines.

nternal combustien engines in general Vand especially' the vlarge engines mentioned must be readily accessible. Particularly easy ,dismantling and removal oi diiferent parts, also internal parts, I

isx also of the utmost importance, as it renders replacement and repair work much easier. The invention aims at imprving existing engine construction in this respect. v

According to the invention therefore the end of the cylinder eitendin'g into the scavenging air chamber is made as a separate and removable part', whereas the said chamber is provided laterally to that part with closable inspection or ntting holes and the supply means for the scavenging air are situated so as to make the said holes freely accessible.

AI-Ieretoiore the end of the cylinder liner ina single acting four stroke internal combustion engine of special design has been made already as a separate and removable part and in this engine the same possibility of inspection and removal of the piston exists. In two stroke engines of normal design it cannot be used,l however, due to the great length of the pistons therein. It has also to be taken into consideration, that in two stroke engines the cylinder ports are situated in the separate and removable end of thecylinder. These ports df course must Vbe connected to corresponding conduits. Due to this the possibility of easy inspection and removal is lost. When applied, however, to a two stroke engine of the above mentioned type the objections referred to will not eXist, on the one hand because such engine may have a short piston and on the other hand because in this engine the end oi the liner extends freely into the scavenging air chamber, with which the cylinder ports are in free communication and from which the end of the liner may be freely removed.

In the drawings an embodiment of the invention has been illustrated.

Figure 1 is a, sectional elevation of a vertical engine, showing a cylinder in section, whereas Figure 2 illustrates the piston on a somewhat larger saaie snowing the removai and inspection thereof.

The frame of crank casing 2 is mounteden the foundation i. i scavenging air 'chamber 3 is 1e: cated eii the casing 2 and ineeyiinder jacket 4 isf located on the chamber 3. Within the jacket 4 the cylinder liner 5 is mounted which is attached at its top` and is capable of expanding ariiallv Within the cylinder jacket A1i. The @minder is closed at itsv top by e; cover s carrying the outlet members. Iii order to enable duick scavenging'f the cylinder a large outlet is necessary; which attains its iaimiin opening capacity within a very short time. Fr this reason the oiitlt rheinbers are divided into foii-r or siii o'iitlet valves which are grouped abdiittliecentre of the cover; where the combustion il injection means is liti- '1 cated. Due to this arrangement a larger t6 valve circumference is obtained than by the of only one valve, 'so that the initial passage d ing the time the Valve is lifted becomes larg r', The outlet valves@ as mentioned are moved together by means of a lever 8, which is driven from the earn shaftl Yi).

The outlet chamber within the cover is con-l nected tothe dutlet conduit IG.

T he'eyiiriueii wsu' is' provided with scavenging' ports l2 near the lowest position of the pistn' I3. The pistoni 3 is so short that the scavenging prts l2 are opened by both the upward and downward strokes. The scavenging nports open into scavenging air chamber 3 An engine of this type shows a very low'overall height.

The piston i3 is removably connected to vtheK piston ro'd, I4, whichends at the cross head I movable along a guide i6. rlhe connecting `rfid il' connects the cross head i5 to' the crank I8 of the crank shaft i9.

The scavenging air chamber 3 is closed at the bottom. and thus separated from the crank case]w by means of a `partition 255. The piston rod I 4 passes through a stufng-box 2| in the partition20. i

The lower end 25 of the, liner 5, wh'ich contains nie scavenging ports i2 and which extends freiify into the scavenging air chamber 3 is made as a separate part removable from the liner 5. It may be connected to the main part of the liner by means of bolts or studs. After detaching the said separate part 25 may be lowered until it stands on the partition 20. Then such a gap will have been formed in the liner that at least a part of the piston I3 will be exposed, so as to enable the piston rings 26 to be inspected, and if necessary removed and replaced, without removal of the piston itself. The scavenging air chamber for this reason is provided with rather large plates 2l, 28 by the removal of which it can be opened fully (see right hand part of Figure 2').

Sometimes it will be possible by lowering the separate end 25 of the liner to enlarge the gap in the cylinder liner to such an extent that the piston I3 after having been disconnected from the piston rod I4 can be removed sidewardly out of the engine as a whole, as indicated by dotted lines at 29. If the lower end of the liner cannot be lowered to such an extent, the piston I3 can be removed sidewards from the scavenging air chamber 3 together with the said lower end 25. Also in this manner a very simple method of removing the piston is obtained. It is illustrated on the left hand part of Figure 2.

In order to permit sideward removal of the piston the plates 21, 28 of the scavenging air chamber must also remain freely accessible. Therefore, the scavenging air pump 30 is situated below the level of the partition 20. It is mounted against the guide I6 and is driven from the cross head I by means of beams 3|. The scavenging airis supplied to the chamber 3 at the bottom through the hole 32 in the partition 20. j When scavenging air pumps are used, which are disposed separate from the engine, e. g. at the front or near end of the engine, the scavenging ,air conduits, which run to the cylinders must remain below the level of the partition 20.

What I claim is:

1. A single acting two stroke cycle internal combustion engine comprising a scavenging air chamber; scavenging air supply means in communication with said chamber; a cylinder having scavenging ports affording communication between it and said chamber, a substantially closed end, an open end,l and a separable part of said cylinder, at the latters open end, extending into said chamber; the said chamber having a closable opening laterally of said separable cylinder part aording access thereto to permit its separation from the remainder of the cylinder, and the said scavenging air supply meansbeing located in a non-blocking position relatively to said opening to render the latter accessible as a means of access to said cylinder part to permit its mentioned separation.

2. A. single acting two stroke cycle internal combustion engine according to claim 1, further including a piston in said cylinder; the said scavenging air chamber and the said separable cylinder part having such relative axial dimensions that a gap is produced in the cylinder wall by such separation in an axial direction through which gap the said piston is accessible for inspection or servicing.

3. A single acting two stroke cycle internal combustion engine according to claim 2, the said gap and opening. being of such dimensions that thepiston may be removed laterally.

4. A single acting two stroke cycle internal combustion engine according to claim l, further including a piston in said cylinder; the piston,

the separable cylinder part, the scavenging air chamber and the latters closable opening being of such lrelative dimensions that said piston and separable Cylinder part may be removed from the engine through said opening.

5. A single acting two stroke cycle internal combustion engine according to claim 1, the said scavenging air supply means being in communication with the said chamber at the wall of the latter which is remote from said cylinder.

6. A single acting two stroke cycle internal combustion engine according to claim 1, further including a scavenging air pump and air conducting means aording communication between said pump and the scavenging chamber; the said pump and conducting means being disposed substantially at one side of a radial plane which includes at least a part of the wall of the scavenging air chamber which is remote from the cylinder, the said pump and conducting means being at the side of said plane opposite to the Side thereof where the said cylinder is located.

7. A single acting two stroke cycle internalv combustion engine according to claim 6, further including a crank casing partly defined by said remote wall of the scavenging air chamber, and a crosshead guide associated with said crank casing; the said pump being attached to said guide.

8. A single acting two stroke cycle internal combustion engine according to claim 6', further including a crank casing partly dened by said remote wall of the scavenging air chamber, a crosshead, guided for reciprocation within said crank casing, the said pump being a reciprocating pumping-element pump, the axis of which extends in the direction of the axis of the said cylinder, and the said engine also including a beam, coacting with said crosshead and pump forV actuating the latter.

9. A single acting two stroke cycle internal combustion engine according to claim 1, thesaid cylinder having outlet means at its closed end.

10. A single acting two stroke cycle internal combustion engine according to claim 2, further including a piston rod extending through a wall of said chamber remote from said cylinder, the said piston being separable from said rod and removable from said engine through said gap and opening.

GERARD JOHAN LUGT.

REFERENCES CITED The following references are of record in the le oi this patent:

UNITED STATES PATENTS Number Name Date 1,366,448 Erickson Jan. 25, 1921 2,254,410 Andresen Sept. 2, 1941 FOREIGN PATENTS Number Country Date 16,445 Great Britain of 1912 

